... 5502 , 221 р . Pettijohn , R.A. , 1986 , Processing water - chemistry data , gulf coast aquifer systems , south - central United States , with a summary of dissolved - solids concentrations and water types : U.S. Geological Survey Water ...
... 5502 ) ; 221 13 14 15 16 17 18 19 20 21 2 2 2 2 2 22 23 ( 3 ) the term " quads per year " means energy use or production of one quadrillion British thermal units per year ; ( 4 ) domestic fossil fuel energy includes coal , oil , and gas ...